Aircraft: CRJ700
Phase of flight: Parked
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Weight And Balance

We had a very busy pre-departure time while preparing for our trip to an unfamiliar destination; including multiple calls for catering cleaning; window wash; and FMS programming for a long and unfamiliar route; including verifying the route on the paper charts. The Captain had informed me that we needed to get off the ground in a hurry as per a chief pilot briefing he received the day prior. The flight attendants had informed me that the 700 had been catered with first class meals. A few minutes before departure the Captain and I went to load the ACARS weight and balance information and tried to select the first class meals in the load manifest. This is where things started to happen really fast. The data came back with a note that the catering selection was unsupported by the aircraft type. This was news to me. I have only been on the 700/900 a few months and had never been told that we had first class meals. I made the assumption that it worked like it was supposed to. By this time the Captain had called for push back and started our push. I told him that we had a problem with the numbers. I tried it again and even with the standard catering selection. We had good numbers with the standard catering; but still the first class meals selection was showing an unsupported aircraft type. At this point the Captain had already started an engine. We did the after start check and started our taxi. While taxiing south the Captain was talking to the Dispatcher. He was going to try to run the numbers with the back up method (I'm really not sure what that meant). Now I had to assume the communication with the Dispatcher trying to get the numbers to work because the Captain was taxiing the aircraft. At this point I felt like I was just along for the ride. The Dispatcher was working the problem from his end to no avail. We ended up adding the weight for a jumpseater to account for the weight of the first class meals. I figure ten bags of 10 LBS ice is about 100 LBS and the glass ware couldn't be more than 90 LBS. In hindsight I think we were too mission focused and should have returned to the gate to make better decisions. The biggest threat in this scenario was the Chief Pilot's call to tell the Captain to hurry. I have never flown with this person before; but I do not think this would have happened without the time pressure placed on him by the company. I understand that this is a company and has to make money; but if a particular flight must be operated in a manner that other flights are not operated under then that a check airman or chief pilot must operate flight. The second biggest threat is that this flight was the first to operate to a new city. The third is that there is no very clear information regarding the selection of First Class meals on the 700 and if this should work or not. I'd say the biggest error is not clarifying if the First Class meals should be aboard the 700. If not; we should have returned to the gate to drop that stuff off.I need to be more assertive with some of our more senior Captains. It is hard to balance the necessary speaking up with good CRM. The company needs to make sure that their technology works they way they think it does. The First Officer aboard a CRJ addressed his concerns about First Class meals being boarded for an inaugural route flight and discovering that the weight and balance program for the aircraft was not programmed to accept the carriage of the heavier meals. The problem was exacerbated by the Captain's recent phone call from a Chief Pilot strongly encouraging 'timely' release and taxi from the gate for takeoff.